import random
import string
list = [] # list本事内置函数，可以取个别的变量名，避免歧义，后面出现问题

for _ in range(100):
    l = [str(random.randint(0,9)) for _ in range(6)]
#   l = [random.randint(0,9) for _ in range(6)]   
    a = string.ascii_lowercase
    s = random.sample(a,10)

    prefix = " "
    last = " "
    
    first = prefix.join(l) # 这里的join出来后的效果是不是有问题
    second = last.join(s)

#    for i in l:
#        prefix += str(i)
#    for j in s:
#        last += str(j)
    
    id = "{}.{}".format(first,second)
    list.append(id)

print(list)
